“Pressing challenges remain” in the FAA’s progression to the Next Generation Air Transportation System (NextGen), says the U.S. Department of Transportation inspector general. In testimony October 5 before the House aviation subcommittee, DOTIG Calvin L. Scovel III cited the FAA’s Metroplex initiative, en route automation modernization (Eram) program and cost and scheduling uncertainties with other programs as potential stumbling blocks. Gerald Dillingham, representing the Government Accountability Office, said the FAA’s most important challenge is to “establish and maintain credibility with NextGen stakeholders,” adding that “this is especially true for airlines.”

The FAA’s optimization of airspace and procedures in the Metroplex initiative embodies a seven-year effort to improve air traffic flows and reduce delays at airports in 21 major metropolitan areas. Scovel said the agency has completed studies at five of the 21 Metroplex locations and started work at two more sites. But the agency has not established “definitive start dates or detailed milestones,” causing concern among airspace users.

Plans call for Lockheed Martin’s Eram system to replace the current Host computer system at 20 FAA air route traffic control centers and provide the future en route automation platform supporting other NextGen systems. Testing at initial deployment sites in Salt Lake City and Seattle revealed “significant software problems” involving the system’s core capabilities of safely managing and separating aircraft, Scovel said. He described the $2.1 billion program as “troubled from the start,” and said further issues may arise at busier en route centers, including Chicago and Los Angeles, where “controllers are not going to be able to engage the same workarounds” they used at the initial sites.

The FAA plans to complete Eram four years late, in 2014, at an additional cost of $330 million. However, a Mitre study and DOT analysis project as much as a six-year delay and a $500 million cost overrun, Scovel said. He warned that ongoing problems with Eram could affect NextGen programs, including automatic dependent surveillance-broadcast (ADS-B), data communications (DataComm) and system wide information management (Swim), as well as complicating the transition to a common automation platform for en route and terminal operations.

The costs, benefits and schedules of ADS-B, DataComm and Swim–three of the six NextGen “transformational” programs–remain uncertain, Scovel said. While the FAA plans to spend nearly $2 billion on them over the next five years, it has yet to produce an “integrated master schedule” and “programs are left with no clear end-state,” he said.